Study of physical function in adolescents with haemophilia: The SO-FIT study.

INTRODUCTION: Contemporary haemophilia care demands Patient-Reported Outcomes. SO-FIT is a UK multi-centre study, assessing self-reported function, health-related quality of life (HRQoL) and joint health in boys with severe haemophilia.

METHODS: Subjective physical function (PedHAL, HEP-Test-Q) and HRQoL (Haemo-QoL Short Form [SF]) were assessed alongside joint health using the objective Haemophilia Joint Health Score (HJHS v2.1). Demographic and clinical data were collected.

RESULTS: Data from 127 boys mean age 12.38 ± 2.5 (range 8-17) treated at 16 sites were analysed. One-hundred-and-thirteen had haemophilia A, 25/9 past/current inhibitor, 124 were treated prophylactically (46.8% primary) and three on-demand. In the preceding 6 months, boys reported median 0 joint bleeds (range 0-8) with a median HJHS score of 1 (range 0-30). Boys reported good physical functioning; HEP-Test-Q (M = 80.32 ± 16.1) showed the highest impairments in the domain "endurance" (72.53 ± 19.1), in PedHAL (M = 85.44 ± 18.9) highest impairments were in the domains "leisure activities & sports" (M = 82.43 ± 23.4) and "lying/sitting/kneeling/standing" (M = 83.22 ± 20.3). Boys reported generally good HRQoL in Haemo-QoL SF SF (M = 22.81 ± 15.0) with highest impairments in the domains "friends" (M = 28.81 ± 30.5) and "sports & school" (M = 26.14 ± 25.1). HJHS revealed low correlations with the Haemo-QoL SF (r = .251, P < .006), the PedHAL (r = -.397, P < .0001) and the HEP-Test-Q (r = -.323, P < .0001). A moderate correlation was seen between HEP-Test-Q and Haemo-QoL SF of r = -.575 (P < .0001) and between PedHAL and Haemo-QoL SFr = -.561 (P < .0001) implying that good perceived physical function is related to good HRQoL.

CONCLUSIONS: The SO-FIT study has demonstrated that children with severe haemophilia in the UK report good HRQoL and have good joint health as reflected in low HJHS scores.